Method of producing a platinum catalyst on refractory oxide support



MnTnonoF PRODUCING A PLATINUM CATA- LYST N REFRACTORY oxmn sorronrClaims. (Cl. 252-442 This invention relates to processes for theconversion of hydrocarbons and to the manufiacture of catalysts for usetherein. It more specifically relates to a process for the reforming ofgasoline in the presence of a catalyst prepared in a specific manner.

The term reforming is well-known in the petroleum industry and refers tothe treatment of gasoline fractions to improve the anti-knockcharacteristics thereof. The petroleum fraction that is rip-graded inreforming may be a full boiling range straight run gasoline having aninitial boiling point within the range of from about 50 F. to about 100F. and an end boiling point within the range of from about 350 F. toabout 425 F. It may also be a natural gasoline as obtained from therefining of natural gases or it may be any selected fraction of thenatural gasoline. The natural gasoline or the natural gasoline fractionwill have an initial boiling point and an end boiling pointsubstantially the same as that of the gasoline hereinbefore described.In the reforming process the gasoline fraction that is selected usuallyis the higher boiling fraction commonly referred to as naphtha andgenerally will have an initial boiling point of from about 150 F. toabout 250 F. and an end boiling pointwithin the range of from about 350F. to about 425 F. The catalyst of the present invention may also beapplied to the reforming of cracked gasoline or mixtures of cracked andstraight run and/or natural gasoline. Reference to gasoline in thepresent specification and claims therefore means a full boiling rangegasoline or any fraction thereof and also that the gasoline fraction maycontain components boiling above the gasoline range.

In the reforming process there are four major reactions.

The first is an aromatization reaction in which naphthene hydrocarbonsare converted to aromatics. Thesecond is a dehydrocyclization reactionin which the straight chain or slightly branched chain parafiins arecyclicized to form aromatics. Third is an isomerization reaction inwhich straight chain or slightly branched chain paraifins are convertedto more branched chain parafiins. This reaction occurs as a result of astrain put upon a carbon to carbon bond so that there is a shift of acarbon atom in the molecule to form a more branched chain molecule. inthis specific reaction there is no change of molecular weight. Thereaction may also be characterized as increasing the number of methylgroups in the hydrocarbon molecule. The fourth is a cracking reaction inwhich the heavier straight chain or slightly branched chain parafi'ins,which have low antiknock characteristics, 18.16 converted to lighterstraight chain or branched chain paraffins which have higher antiknockcharacteristics. When this last reaction is conducted in the presence ofhydrogen, the unsaturated hydrocarbon which is formed as a result of thecracking operation is saturated t-o the paraflin by reaction withhydrogen in the presence of the reforming catalyst. The cracking orsplitting of the carbon to carbon bond is one of the more importantreactions in a successful reforming process. It is necessary that thesplitting of the ited States Patent "ice carbon to carbon bond becontrolled so that there is no ex cessive formation of normally gaseousproducts. For e3 ample, it would be possible to crack a C10 hydrocarbonto form ten molecules of methane, however, unless methane is thespecifically desired product, it would be uneconom-f ical in a reformingprocess to crack the C10 hydrocarbon to form methane. It is moredesirable to crack'ta Ci'q hydrccznbon so that two molecules of pentaneare formed and it would be still more desirable if during the reaction,isomerization would simultaneously take place so that the productobtained would be isopentane. It is an objectv of the present inventionto provide a catalyst wherein the, cracking activity is controlled andselective so that ex-- cessive amounts of normally gaseous products arenot produced inareforming process. p

Uncontrolled or non-selective cracking results in the more rapidformation of larger quantities of coke or carbonaceous matter whichdeposits on the catalyst and decreases or destroys its activity tocatalyze the desired reactions. This in turn results in shorterprocessing cycles or periods with the necessity of more frequentregeneration of the catalyst by burning the carbonaceous productstherefrom, or should the catalyst activity be destroyed it, will benecessary to shut down the unit to remove the old catalyst and repiaceit with new catalyst.

l lydrocracking of parafiins and dehydrogenation of naphthenes are theprincipal reactions that are promoted by these catalysts which arecapable of increasing the octane number of gasoline and naphtha tovalues that are substantially higher than those that ordinarilycan bereached by thermal reforming. In addition the yield octane numberrelationships realized with these catalysts are much better than are thecorresponding relationships obtained in thermal reforming and in most ofthe prior By appropriate selection, or" operating conditions thesecatalysts can be used for a number of months and even yearswithoutregeneration'...

catalytic reforming processes.

While the catalyst-of the presentinvention is particu-. larly suitablefor the reforming of gasoline it is under-- stood that this novelcatalyst may be utilized for the conversion ofother hydrocarbonfractions. Thus the oat aly st may be used for the dehydrogenation ofselected hydrocarbon fractions such as naphthenes to produce aromaticsthe dehydrogenation of parafiins to producethe corresponding olefins,the dehydrogenation of monoolefins to diolefins, etc.

sion of normalhexane to benzene. The catalystmay also.

be used to effect isomerization reactions and hydrogenation reactions,including non-destructive hydrogenation and destructive hydrogenation.In still another embodiment the catalyst of the present invention may beused for efiecting oxidation of hydrocarbons to form the corre-vspending oxide and desulfurizing sulfur-containing fractions.

method of uniformly distributing an acidic component throughout aninorganic refractory oxide whichcom prises forming particles containingsaid. acidic com.-

ponent and said inorganic refractoryoxide, calcining said particles at atemperature of from about 400 F. to about 1600 R, and subsequentlysubmerging said calcined particles in liquid Water in an amount and fora time sufiicient to distribute said acidic component uniformly ganicrefractory oxide, calcining the composite at atemw perature of fromabout 400 Etc about 1600? F., sub merging said calcined compositeinliquid water in an The catalyst may also be utilized to effectdehydrocyclization reactions such asthe conver: 1

In one embodiment the present invention relates to a V amount and for atime sufficient to distribute said acidic component uniformly throughoutsaid composite and combining therewith an active metal component.

In a specific embodiment the present invention relates to a method ofpreparing a catalyst which comprises combininga halogen with alumina inan amount of from about 0.1% to about 8% by weight of said alumina on adry basis, calcining the composite at a temperature of from about 400 F.to about 1600 F., submerging said calcined particles in liquid water fora period of at least one minute thereby distributing said halogenuniformly throughout said particles, subsequently commingling with saidparticles a solution of a platinum compound in anamount to form a finalcatalyst containing from about 0.01% to about 1% by weight of platinumand heating the composite at a temperature of from about 500 F. to about1100 F. 7

In a further embodiment the present invention relates to a process forthe conversion of a hydrocarbon which comprises subjecting saidhydrocarbon to contact at conversion conditions with a catalyst preparedby calcining a composite of an acidic component and an inorganicrefractory oxide at a temperature of from about 400 F. to about 1600 F.,submerging said calcined composite in liquid Water in an amount and fora time suflicient to distribute said acidic component uniformlythroughout said composite and combining therewith an active metalcomponent.

In another specific embodiment the present invention relates to aprocess for reforming a straight run gasoline fraction which comprisessubjecting said fraction to contact at a temperature of from about 500F. to about 1000 F., a pressure of from about 50 to about 1000 poundsper square inch, and a weight hourly space velocity of from about 0.5 toabout in the presence of from about 0.5 to about 20 mols of hydrogen permol of hydrocarbon with a catalyst prepared by combining a halogen withalumina in an amount of from about 0.1% to about 8% by weight of saidalumina on a dry basis, calcining the composite at a temperature of fromabout 400 F. to about 1600 F., submerging said calcined particles inliquid Water for a period of at least one minute ,thereby' distributingsaid halogen uniformly throughout said particles, subsequentlycommingling with said particles a solution of a platinum compound in anamount to form a final catalyst containing from about 0.01% to about 1%by weight of platinum and heating the composite at a temperature of fromabout 500 F to about 1100 F.

In aceordancewith the present invention a composite of an acidiccomponent and an inorganic refractory oxide, whlch 1s usually thecracking-component, is calcined at a temperature of from about 400 F. toabout 1600 F. pr or .to further treatment. One cracking componentcomprises at least two inorganic refractory oxides. Another crackingcomponent comprises a refractory inorganic oxide and halogen. Thehalogen is the acidic component in this catalyst. Suitable but notnecessarily equivalent inorganic refractory oxides comprise the oxidesof aluminum, silicon, zirconium, zinc, titanium, magnesium, cadmium,gallium, iridium, thallium, germanium, tin, cerium, lead, thorium,vanadium, columbium, tantalum, chromium, molybdenum, tungsten, uranium,manganese, etc. Preferred combinations for the cracking component whichcomprises at least two inorganic refractory oxides are alumina-silica,alumina-titania, alumina-boron oxide, silica-magnesia, silica zirconia,silicathoria, etc. The preferred oxides for the cracking component whichcomprises a refractory oxide and halogen are the oxides of aluminum,zirconium, zinc, titanium, magnesium, and cadmium, however, notnecessarily with equivalent results. Combinations of .two or'more ofthese oxides, for example alumina-silica, alumina-zirconia, etc., may beused for compositing withthe halogen within the scope of this invention,but again not necessarily with equivalent results. The crackingcomponent preferably contains halogen since it has been found that thehalogen will more readily distribute itself uniformly throughout theother component or components of the catalyst when submerged in liquidwater for a sufiicient period of time.

In the alumina-silica composite it is the particular association of thealumina with the silica that gives the catalyst its acidic and crackingproperties. Silica alone or alumina alone has little if any crackingactivity, however, for example, starting with alumina, when silica iscomposited therewith the fact that silica is added gives the catalystits acidic and cracking properties and therefore the silica may betermed the acidic component. Likewise starting with silica and addingalumina, alumina may likewise be called an acidic component.

he halogen includes fluorine, chlorine, iodine, and bromine. Thepreferred halogen comprises fluorine and chlorine. In general, fluorineappears to be less easily removed from the catalyst and of higheractivity and, therefore, is preferred in many cases. It is understoodthat the halogen may comprise a mixture of two or more of the halogens,a preferred mixture comprising fluorine and chlorine.

Another component of the catalyst comprises a metal or a compound of ametal selected from group VIII of the periodic table. While platinum andits compounds are preferred components it is understood that othersuitable members of group VIII and particularly of the platinum groupmay be employed. These other components may include, although notnecessarily with equivalent results, the metals or compounds of nickel,cobalt, palladium, iridium, etc. or mixtures of two or more thereof.

It is understood that the various combinations of components which maybe prepared and used in accordance with the present invention are notnecessarily equivalent.

In general, the refractory oxide or mixture of the oxides will comprisea major proportion of the catalyst and thus" will range from about 75%to about 99.8% by weight of the catalyst composite. The halogen willgenerally be used in amounts of from about 0.1% to about 10% by weightof the final catalyst. When fluorine is the halogen it will be used inamounts of from about 0.1% to about 5% by weight of the final catalystand when chlorine is the halogen it will generally be used in amounts offrom about 0.1% to about 8% by weight of the final catalyst. Asmentioned the halogen may comprise a mixture of two or more halogens andthe total amount of halogen will generally be within the ranges hereinset forth..

The concentration of the metal component selected from the metals andcompounds of the metals in group VIII of the'periodic table willgenerally be comparatively lower than the inorganic refractory oxidecomponents. The concentration of the metal component selected from groupVIII of the periodic table will generally be from about 0.01% to' about10% by weight of the final catalyst.

t. is understood that when desired two or-more metals or compounds ofmetals of this group may lie-utilized in the catalyst composite.

The cracking component of the catalyst of the present invention may bemade in any suitable manner including separate,successive, orcoprecipitation methods. The refractory oxide may beprepared in anysuitable manner. For example, alumina may be prepared by adding arcagent such as ammonium hydroxide, ammonium carbonate, etc. to a saltof aluminum such as aluminum chloride, aluminum nitrate, aluminumacetate, etc., in an amount to form aluminum hydroxide, which upondrying is converted to alumina. In the present specification and claimsthe aluminum hydroxide is referred to as. alumina in order that thepercentages are based on the alumina free of combined water. It has beenfound that a chloride of aluminum is generally preferred as the aluminumsalt to be used, not only for convenience in subsequent washing andfiltering procedures but also it appears to give best results. After thealumina has been formed it .is generally washed to remove solubleimpurities. Usual Washing procedures comprise washing with water eitherin combination with filtering or as separate steps. It has been foundthat filtration of the alumina is improved when the Wash water containsa small amount of ammonium hydroxide. The ordinary washing may generallydepend upon whether ail or a part of the chlorine is to be retained inthe catalyst composite. When chlorine is not desired the alumina iswashed thoroughly to remove substantially all of the chlorine. On theother hand, if part of the chlorine is to be retained in thecatalyst'the washing is less severe. In general, it is preferred to washthe alumina thoroughly and if chlorine is desired'it is added as aseparate step because better control of the amount of chlorine isobtained in this manner. Alumina spheres may be continuously prepared bypassing droplets of an alumina sol into an oil bath maintained at anelevated temperature and retaining the droplets in said oil bath untilthe droplets set to firm gel spheres. The spheres are continuouslywithdrawn from the oil bath and immediately thereafter aged prior tobeing contacted with water or aqueous solution.

Silica may be prepared in any suitable manner, one method being tocommingle water glass and a mineral acid under conditions to precipitatea silica hydrogel. The

. silica hydrogel is washed with Water containing a small amount ofelectrolyte to remove sodium ions. Oxides of other compounds may beprepared by reacting a basic reagent such as ammonium hydroxide,ammonium carbonate, etc., with an acid salt solutionof the metal as, forexample, the chloride, sulfate, nitrate, etc., or by adding an acid toan alkali salt of the metal as, for example, commingling sulfuric acidwith sodium aluminate, etc. Usually the metal oxide will be washed andfiltered whichmay be done in the same or separate steps and may beeffected in the presence of an acid or a base as desired. When it isdesired to prepare the catalyst in the form of particles of uniform sizeand shape, this may readily be accomplished by grinding the partiallydried oxide cake with a suitable lubricant such as stearic acid, rosin,graphite, etc. and then forming the particles in any suitable pelletingor extrusion apparatus.

When the cracking component comprises at least two refractory inorganicoxides the composite may be prepared in any suitable manner includingseparate, successive, or coprecipitation methods. In the separateprecipitation method the oxidesareprecipitated separately and thenmixed, preferably in the wet state. When successivepreeipitation methodsare employed the first refrac tory inorganic oxide is precipitated, ashereinbefore 'set forth, and then the wet slurry, either with or Withoutprior Washing may be, composited with-a salt of the other component andprecipitation of the oxide is effected by the addition of a suitablebase or acid as required. This composite may then be dried and formedinto particles.

Cracking components comprising silica-alumina andsilica-alumina-zirconia are preferably manufactured by comminglinganacidsuch as hydrochloric acid, sulfuric acid, etc., with commercial waterglass under. conditions to precipitate silica, washing with acidulatedwater or otherwise to remove sodium ions, commingling with an aluminumsalt such as aluminum chloride, aluminum sulfate, aluminum nitrateand/or zirconium salt, etc., and either adding a basicprecipitant suchas ammonium hydroxide to precipitate alumina and/or zirconia, or formingthe desired oxide or oxides by thermal decomposition of the salt as thecase may permit. The silicaalumina-zirconia crackingcomponent may beformed by adding the aluminum and/or ,zirconium .salts together orseparately. The other crtkkingcomponets may .be

prepared in a similar manner, however, not necessarily with equivalentresults.

The halogen may be added to the catalyst in any suitable manner andeither before or after precipitation of the oxide. While the halogen maybe utilized as such, it generally is preferred to utilize the halogen asan aqueous solution of the hydrogen halide for ease in handling. In thepreferred method the halogen is added to the refractory oxide before theother components are composited therewith. When alumina is the selectedrefractory oxide the halogen is preferably incorporated into the aluminabefore forming into particles and thismay be accomplished by the use ofan acid such as hydrogen fluoride, hydrogen chloride, hydrogen bromide,and/or hydrogen iodide. In some cases volatile salts such as ammoniumfluoride, ammonium chloride, etc., may be employed. In any event, theamount of halogen will be in the range of from about 0.1% to about 10%by weight of the final catalyst. Chemically combined fluorine appears tobe more active and therefore will be used within the range of from about0.1% to about 5% by weight of the refractory oxide on a dry basis. Thechlorine content will generally be within the range of from about 0.1%to about 8% and preferably from about 0.2% to about 5% by weight of thefinal catalyst on a dry basis.

in the prior art various methods of achieving uniform cracking activityon the various particles of the catalyst have been discussed. It isdesirable that the cracking component be uniformly distributedthroughout the catalyst mass in order that a better control of thereactions may be had and, further, I have found that when a uniformcracking component is further composited with an active metal component,that it is necessary that the cracking component have uniformitythroughout the entire catalystmass in order to have the metal componenturdformly distributed throughout the catalyst mass. For example, halogenmay be composited with several pounds of alumina spheres and uponindividual examination of the spheres it may be found that the halogenis not uniformly distributed therethrough,that is the halogenconcentration on some of the spheres will be higher than on others. Thecracking activity of the catalyst mass, therefore, will be non-uniformand further when this composite is further composited with an activemetal component the active metal component will not be uniformlydistributed throughout the entire mass. For this reason it is seenthatit is desirable to have the halogen uniformly distributed.

I have invented a method of uniformly distributing a halogen throughoutan inorganic refractory oxide which comprises forming particlescontaining said halogen and said inorganic refractory oxide, calciningsaid particles at a. temperature of from about 400 F. to about 1600 F.,and subsequently submerging said calcined particles in liquid water inan amount and for a time sufiici'ent to distribute said halogenuniformly throughout said particles. When the particles of halogen andinorganic refractory oxide are submerged in water prior to calcination,the halogen does not readily distribute'itself throughout the inorganicrefractory oxide. It is my theory, hoW- ever, I do not intend myinvention to be limited thereto, that the halogen prior toimpregnation-is in a form wherein it is intimately combined with thealumina and is tenaceously held. After the calcination, however, itappears that the halogen is in a more mobile formand when, subsequent tothe calcination, the particles are contacted with liquid Water, thehalogen more readily distributes itself uniformly throughout theinorganic refractory oxide mass.

As herein mentioned the composite of halogen and the inorganicrefractory oxide is subjected to a calcining operation prior tosubmerging in .liquid water. The calcination is conducted at atemperature of from about 400 .F. to about 1600" F. or more but usuallynotin excess of 1400 F. The heattreatment or-calcinationmaybeconductedin an oxidizing atmosphere such as air or oxygen,

avreducing atmosphere such as hydrogen or an inert atmosphere such asnitrogen, etc. In some cases the calcination may take place in airfollowed by heat treatment in the presence of hydrogen or the reverseprocedure may be used. 'The calcination is more usually and preferablyconducted in air or other oxygen-containing gas. The periods of thecalcination may vary widely from about as low as minutes to 8 hours ormore.

In accordance with the present invention after this calcinationtreatment the particles are submerged in liquid water in an amount andfor a time sufficient to distribute said acidic component uniformlythroughout said particles. It is not suflicient that the calcinedparticles merely be wetted since in this manner the halogen on oneparticlemay not'shift or migrate to other adjacent particles. It is thusnecessary that a water bridge occur between all of the particles whichare to be made uniform and the most convenient and simplest method ofachieving this result is to completely submerge the particles in liquidwater. The pills may be submerged by adding them to water or water maybe added to the pills.

The distributing of the halogen or other acidic component throughout theinorganic refractory oxide thus necessarily takes place in liquid Waterand the temperatures that the liquid water may be utilized at range fromthe freezing point of water of 32 F. to the critical point of water of705 F. When temperatures above the boiling point of water are utilizedit is necessary to maintain a pressure on the system suflicient to keepthe water in the liquid phase. The time that is required to achieve thisuniform distribution varies inversely with the temperature. At lowertemperatures longer contacting times are required and conversely withhigher temperatures shorter processing times may be used. In general atroom temperature the particles are submerged in water for a period ofabout 8 hours and at higher temperatures of from about 175 F. to about300 F. the time of submerging of the particles in liquid water will beabout one minute. The time the particles are submerged, therefore, is atleast one minute.

After the halogen or other acidic component has accordingly beenuniformly distributed throughout the inorganic refractory oxide mass,the active metal component is composited with the cracking component. Ina preferred embodiment of the present invention platinum is subsequentlycomposited with the cracking component generally in an amount of fromabout 0.01% to about 1% by weight of the catalyst. Platinum is aparticularly desirable metal component to be'incorporated into thecatalyst since catalysts containing low concentrations of platinum havebeen found to be very active, especially when the catalyst is to be usedin reforming operations. The metal component selected from metals andcompounds of the metals in group VIII of the periodic table may beincorporated into the catalyst in any suitable manner and may becomposited immediately subsequent to submerging the calcined particlesin liquid water or the calcined particles may be submerged in liquid.water and then dried or calcined before adding the active metalcomponent.

When platinum is the selected active metal component one method ofintroduction is to form a separate solution of chloroplatinic acid andwater and to introduce hydrogen sulfide into this solution at roomtemperature until the chloroplatinica-cid solution reaches a constantcoloration, that is there will be no change in color upon addition ofmore hydrogen sulfide. A chloroplatinic acid solution is'normally lightyellow and upon addition of hydro gen sulfide gas turns to a dark browncolor. Apparently the chloroplatinic acid and hydrogen sulfide react toform one or more complexes or chemical compounds. The brown solution ofchloroplatinicacid and hydrogen sulfide may then be commingled with theother components of the catalyst as hereinbeforeset forth,

Another method of introducing the platinum into the catalyst is to forma separate aqueous solution of chloro platinic acid and add ammoniumhydroxide to give a solu' tion having a pH between the range of fromabout 5 to about 10. This solution is then commingled with the othercomponents of the catalyst. Although the platinum is preferablyintroduced as a solution of chloroplatinic acid other suitable platinumsolutions may be employed such as solutions, colloidal solutions orsuspensions of platinum cyanide, platinum hydroxide, platinum oxide,platinum sulfide, etc. In cases where these solutions are not soluble inwater at the temperatures used other suitable solvents such as alcohol,ethers, etc., may be utilized.- The platinum appears to enter into apeculiar association with the other components of the catalyst andthereby serves to improve the antiknock characteristics of the productobtained in processes in which the catalyst is used. While platinum is apreferred component it is understood that other suitable componentsselected from the metals and compounds of the metals in group VIII ofthe periodic table may be employed. These components include, althoughnot necessarily with equivalent results, nickel, cobalt, ruthenium,rhodium, osmium, iridium, palladium, etc., compounds thereof, ormixtures of two or more of these metals or compounds of these metals.

The concentration of the metal component selected from group VIII willvary according to the particular component selected and the conversionprocess in which it is to be used, however, the concentration generallywill lie within the range of from about 0.01% to about 10% by weight ofthe final catalyst (calculated as the metal).

The catalyst composite after all of the components of the catalyst arepresent therein is usually subjected to a high temperature treatment.The heat treatment or calcination may be conducted in anoxidizing-atmosphere, a reducing atmosphere such as hydrogen, methaneetc., or an inert atmosphere such as nitrogen etc., however, thecalcination is preferably conducted in air or other oxygencontaininggas. The final calcination is performed at a temperature within therange of from about 500 F. to about 1100 F. The preferred heatingperiods are from about 1 to 8 hours or more.

Although the catalyst of the present invention will have a long life itmay be necessary to regenerate the catalyst after long periods ofservice. The regeneration may be effected by treatment with air or otheroxygencontaining gas to burn the carbonaceous material therefrom. Ingeneral it is preferred to control the regenera tion temperature not toexceed about 1100 F.

As hereinbefore set forth these catalysts are particularly suitable foruse in the reforming of gasoline or fractions thereof. The exactoperating conditions depend upon the character of the charging stock aswell as the activity of the catalyst being used. However, the conditionsusually will be in the following ranges: temperature from about 500 F.to about 1000 F., a pressure of from about 50 to about 1000 pounds persquare inch or more, weight hourly space velocity (defined as the weightof oil per hour per weight of catalyst in the reaction zone) of fromabout'0.5 to about 20 or more. The reforming is preferably effected inthe presence of hydrogen which may be introduced from an extraneoussource or recycled from within the process. In the preferred mode ofoperation sutficient hydrogen is produced and recycled so that noextraneous source of hydrogen is necessary. A hydrogen to hydrocarbonmol ratio of from about 0.5 to about 20 or more mols of hydrogen per molof hydrocarbon is usual.

Processes using the catalyst of the present invention may be effected inany suitable equipment. The catalyst may be deposited as a fixed bed ina reactor and the hydrocarbons to be treated are passed therethrough ineither upward or downward flow. The catalyst may be used in a fluidizedtype of operation in which the catalyst and hydrocarbons are maintainedin a state of turbulence under hindered settling conditions or afiuidized fixed bed type of operationmay housed in whichthecatalyst andhydrocarbons are maintained in a stateof-turbulence under hinderedsettling conditions but where catalyst is not withdrawn from orintroduced into the reaction-zone during the processing cycle. Thecatalyst may also be used in the moving bed type of process in which thecatalyst and hydrocarbons are passed either in concurrent orcountercurrent now through a reaction zone and the catalyst may also beused in the suspensoid type of operation in which the catalyst andhydrocarbons are passed as a slurry through the reaction zone. Thereactants from any of the hereinbefore mentioned reaction zones arenormally subjected to a further treatment such as the stabilization ofthe product to separate normally gaseous products therefrom and toobtain a final reformed product of the desired volatility and vaporpressure.

The following example is given to illustrate my invention but is notintended for the purpose of unduly limiting the generally broad scope ofthe present invention.

Example An alumina sol was prepared by digesting aluminum metal in adilute hydrochloric acid solution at an elevated temperature. Theresultant sol contained from about 26% to about 28% A1203. Ahexamethylene tetramine solution was prepared by adding 291 grams ofhexamethylene tetramine to form 1 liter of solution. The sol andsolution were passed, each at an equal rate, into a mixer. The mixturewas then passed through a nozzle and into a forming chamber filled withNujol. The forming chamber was maintained at a temperature of 195 F. Thedroplets assumed substantially spherical shape during passage throughthe Nujol and were removed from the lower portion of the forming chamberby means of a stream of Nujol maintained at a temperature of 195 F. TheNujol stream containing the spheres was passed into another zone inwhich a level of Nujol was maintained. This second zone likewise wasmain tained at a temperature of about 195 F. The spheres were maintainedin this zone for 16 hours.

The partially aged spheres were then further aged in an ammoniumhydroxide solution for 24 hours at 203 F. The aging solution was thendrained and the spheres were washed with water containing a small amountof ammonium hydroxide. A 4.8% aqueous solution of hydrogen fluoride wasadded in an amount to produce a final catalyst containing 0.45% combinedfluorine by weight. The spheres were then further washed with water. Thewashed spheres were then partially dried at a temperature of 248 F. Thedried spheres were immediately calcined thereafter at a temperature of1200 F. for 3 hours.

A random sample of approximately 20 cc. of the calcined base was dividedinto two equal portions. One sample portion was covered with brom thymolblue indicator solution. After about one minute the indicator wasremoved from the spheres and they were given a water rinse. The sphereswere then noted to be colored in varying degrees between yellow and blueindicating a wide range in acidity in the limits of the indicator (6-7.5pH).

The other sample portion was placed in a test tube and covered with coldwater. The water and sample were heated to about 210 F. and maintainedthere for approximately one minute. The total time of submersion of thepills was about two minutes. The pills were then cooled to roomtemperature.

These spheres were then tested with brom thymol blue as was the firstportion of the sample. In this case the spheres were noted to beuniformly blue in coloration.

The results of the above experiment show that the halogen, or acidiccomponent of the catalyst will uniformly distribute itself throughout acalcined halogen-inorganic refractory oxide composite when submerged inliquid water.

When the first batch "of spheres is further impregnated with achloroplatinic acid solution the calcined catalyst will have variousconcentrations of platimrm on the spheres when one sphere is compared toanother and when used in a reforming operation the catalyst will showvarying degrees of activity when one sphere is compared to another, dueto variations in the halogen and platinum concentrations.

When the second batch of spheres is impregnated with a chloroplatinicacid solution the platinum is uniformly distributed throughout thespheres and when used in a reforming operation the spheres will haveuniform activity from one sphere to the other.

I claim as my invention:

1. A method of manufacturing a catalyst which comprises compositing ahalogen component with an inorganic refractory oxide, calcining thecomposite at a temperature of from about 400 F. to about 1600 F.,submerging said calcined composite in liquid water in an amount and fora time sufficient to distribute said halogen component uniformlythroughout said composite, and subsequently adding to the thus treatedcomposite an active metal component containing a metal in group VIII ofthe periodic table.

2. The method of claim 1 further characterized in that said halogencomponent comprises fluorine.

3. The method of claim 1 further characterized in that said inorganicrefractory oxide comprises alumina.

4. The method of claim 1 further characterized in that said active metalcomponent comprises platinum.

5. A method of preparing a catalyst which comprises forming particles ofa halogen component and an inorganic refractory oxide, calcining saidparticles at a temperature of from about 400 F. to about 1600 F.,contacting said calcined particles with liquid water in an amount andfor a time sufiicient to distribute said halogen component uniformlythroughout said particles, subsequently adding to the thus treatedparticles an active metal component selected from the group consistingof platinum and palladium and compounds thereof in an amount to form afinal catalyst containing from about 0.01% to about 1% by weight of saidmetal component (calculated as the metal), and heating the composite ata temperature of from about 500 F. to about 1100 F.

6. A method of preparing a catalyst which comprises combining a halogenwith alumina in an amount of from about 0.1% to about 8% by weight ofsaid alumina on a dry basis, calcining the composite at a temperature offrom about 400 F. to about 1600 F., submerging said calcined compositein liquid Water for a period of at least one minute, therebydistributing said halogen uniformly throughout said composite,subsequently commingling with the thus treated composite a solution of aplatinum compound in an amount to form a final catalyst containing fromabout 0.01% to about 1% by weight of platinum, and heating the compositeat a temperature of from about 500 F. to about 1100" F.

7. The method of claim 6 further characterized in that said halogencomprises fluorine in an amount of from about 0.1% to about 5% by weightof said alumina on a dry basis.

8; The method of claim 6 further characterized in that said halogencomprises chlorine in an amount of from about 0.1% to about 8% by Weightof said alumina on a dry basis.

9. A method of catalyst manufacture which comprises calcining ahalogen-containing refractory oxide at a temperature of from about 400F. to about 1600 F., soaking the calcined material in liquid water for atime sufficient to distribute the halogen uniformly throughout theoxide, and subsequently compositing with the thus treated material anactive catalyst component comprising a metal in group VIII of theperiodic table.

10. A method of catalyst manufacture which comprises calcining ahalogen-containing alumina at a temperature 11 12 of from about 400 F.to about 1600 F., soaking the References Cited in the file of thispatent calcined material in liquid water for a time suflicient to UNITEDSTATES PATENTS distribute the halogen uniformly throughout the alumina,and subsequently compositing platinum with the thus 2,4721) Ha'ensel 1611949 treated halogen-containing alumina. 5 1,136 Haensel 1953 2,667,461Guyer et a1 Jan. 26, 1954

1. A METHOD OF MANUFACTURING A CATALYST WHICH COMPRISES COMPOSITING AHALOGEN COMPONENT WITH AN INORGANIC REFRACTORY OXIDE, CALCINING THECOMPOSITE AT A TEMPERATURE OF FROM ABOUT 400* F. TO ABOUT 1600* F.,SUBMERGING SAID CALCINED COMPOSITE IN LIQUID WATER IN AN AMOUNT AND FORA TIME SUFFICIENT TO DISTRIBUTE SAID HALOGEN COMPONENT UNIFORMLYTHROUGHOUT SAID COMPOSITE, AND SUBSEQUENTLY ADDING TO THE THUS TREATEDCOMPOSITE AN ACTIVE METAL COMPONENT CONTAINING A METAL IN GROUP VIII OFTHE PERIODIC TABLE.